Co-assembly and self-sorting are not mutually exclusive in enantiomeric peptide systems.

Co-assembly and self-sorting in multicomponent systems are typically treated as mutually exclusive outcomes. Here, we show that this distinction is incomplete. Using enantiomeric peptide nanotubes, we demonstrate that a single co-assembled structure forms only at an equimolar composition, yet remains internally self-sorted into compositionally distinct domains. Contrast-matched neutron scattering directly reveals this segregation and shows that the co-assembled structures adopt layered architectures rather than simple molecular-level mixing. These results establish that co-assembly and self-sorting can coexist within a single supramolecular object across length scales, providing a general framework for understanding and controlling multicomponent self-assembly.